Swirl valves

The present disclosure relates to flow control, and more particularly to flow control such as for controlling flow of fuel in aircraft fuel injection and the like.

Certain valves require only adjustment of the flow over a given range and not complete control, e.g. they do not have to completely close off flow. Some valves have springs with a balanced pressure force to control the open area of the valve. Some valves have integral check valves. Certain valves can be electronically controlled through a solenoid, stepper motor, or the like.

Spool valves are currently used in fuel injectors for gas turbine engines to control the flow to a circuit for a given inlet pressure. They can be costly to make because of multiple factors such as the following. They are often made using a carefully toleranced port opening to allow a certain amount of flow for a given pressure. The spool valve is typically match ground with the sleeve to reduce the amount of leakage which bypasses the metering port. On the other hand, electronic solenoid type valves typically need large power forces to overcome flow pressure to adjust the spool window.

The conventional techniques have been considered satisfactory for their intended purpose. However, there is an ever present need for improved systems and methods for reliable and cost effective valving, such as for valves used in fuel injectors for gas turbine engines and the like. This disclosure provides a solution for this need.

A valve system includes a spin chamber having an outlet drain configured to allow flow out of the spin chamber. A main spin surface of the spin chamber is defined around the outlet drain. A directional jet system is in fluid communication with the spin chamber. The directional jet system includes a member that is configured to move between a first position for directing a tangential flow around the drain, and a second position for directing a radial flow toward the drain.

The directional jet system can include a jet orifice that feeds into the spin chamber. The spin chamber may include only one inlet, namely the jet orifice. The spin chamber may include only one outlet, namely the outlet drain.

The jet member can include a jet tube. The jet orifice can be defined at an outlet end of the jet tube. The directional jet system can be configured to rotate the jet tube to direct the jet orifice more toward a periphery of the spin chamber in the first position relative to the second position. The directional jet system can be configured to rotate the jet tube to direct the jet orifice more toward the drain outlet in the second position relative to the first position. The directional jet system can include one or more inlets configured to feed into the jet tube configured to supply fluid to the jet orifice. The directional jet system can include a rotational actuator operatively connected to rotate the jet tube between the first position and the second position. The directional jet system can include a housing with a main inlet in fluid communication with an interior of the housing. The jet tube can include at least one inlet inside the housing in fluid communication to receive flow from the interior of the housing into the jet tube. The rotational actuator can be inside the housing. The rotational actuator can be operatively connected to rotate the jet tube between the first position and the second position around a rotation axis parallel to an axis defined by the drain outlet. The main spin surface can be planar. The main spin surface can be conical, converging towards the drain outlet.

The directional jet system can include a housing with a main inlet in fluid communication with an interior of the housing. The jet tube can include at least one inlet inside the housing in fluid communication to receive flow from the interior of the housing into the jet tube. The rotation actuator can be outside of the housing with a shaft extending into housing operatively connected to rotate jet tube inside housing. The main inlet can extend along or parallel to an axis defined by the drain outlet. The rotational actuator can be operatively connected to rotate the jet tube between the first position and the second position around a rotation axis oblique to the axis defined by the drain outlet. The main inlet can extend lateral to an axis defined by the drain outlet. The rotational actuator can be operatively connected to rotate the jet tube between the first position and the second position around a rotation axis oblique to the axis defined by the drain outlet.

The directional jet system can include a seal operatively connected to the spin chamber to seal the jet orifice in a third position of the directional jet system to stop flow into the spin chamber from the directional jet system. The directional jet system can include a check valve operatively connected to the spin chamber to check the jet orifice in a third position of the directional jet system to stop flow into the spin chamber from the directional jet system below a predetermined pressure.

The drain outlet can feed into a hydromechanical piston valve assembly. The drain outlet can feed into the hydromechanical piston valve assembly in series with a main flow passage through the hydromechanical piston valve assembly. The drain outlet can feed into the hydromechanical piston valve assembly in a side stream that is parallel with a main flow passage through the hydromechanical piston valve assembly.

The jet orifice can be fixed relative to the spin chamber. The jet member can include a diverter downstream from the jet orifice. The diverter can be configured to move to divert flow from the jet orifice between the first position and the second position.

A feed arm can be connected in fluid communication with the drain outlet. A spray nozzle can be connected in fluid communication with the feed arm downstream of the drain outlet for issuing a spray.

These and other features of the systems and methods of the subject disclosure will become more readily apparent to those skilled in the art from the following detailed description of the preferred embodiments taken in conjunction with the drawings.

Reference will now be made to the drawings wherein like reference numerals identify similar structural features or aspects of the subject disclosure. For purposes of explanation and illustration, and not limitation, a partial view of an embodiment of a valve system in accordance with the disclosure is shown inand is designated generally by reference character. Other embodiments of systems in accordance with the disclosure, or aspects thereof, are provided in, as will be described. The systems and methods described herein can be used to control flow through a valve system using a directional jet and spin chamber, wherein changing direction of the jet relative to the spin chamber allows for increasing or decreasing flow through the valve system.

The valve systemincludes a spin chamberhaving an outlet drainconfigured to allow flow out of the spin chamber. A main spin surfaceof the spin chamber is defined around the outlet drain, i.e. around an axis A defined through the outlet drain. A directional jet systemis in fluid communication with the spin chamber. The directional jet systemincludes a member that is configured to move between a first position for directing a tangential flow around the drain, e.g. as indicated by the flow arrow in, and a second position for directing a radial flow toward the drain, as indicated by the flow arrow in. Directing the flow in the tangential direction indicated inreduces flow through the valve systemrelative to directing flow in the radial direction of, so rotation of the directional jet ultimately controls how much flow can go through the valve system. Intermediate positions between the tangential and radial positions allow for intermediate flow volumes.

With continued reference to, the directional jet systemincludes a jet orificethat feeds into the spin chamber. The spin chamberneed only include one inlet, namely the jet orifice, and one outlet, namely the outlet drain. The jet member includes a jet tube. The jet orificeis defined at an outlet end of the jet tube. The directional jet systemis configured to rotate the jet tubeabout rotation axis B to direct the jet orificemore toward a periphery of the spin chamber in the first position relative to the second position, for lower flow, highly swirling tangential flow in the spin chamber. The directional jet systemis configured to rotate the jet tubeabout the rotation axis B to direct the jet orificemore toward the drain outletin the second position relative to the first position for higher flow, relatively swirl free flow in the spin chamber. The directional jet systemincludes one or more inlets, e.g. tangential inletsconfigured to feed into the jet tubeto supply fluid to the jet orifice.

With continued reference to, the directional jet systemincludes a rotational actuatoroperatively connected to rotate the jet tubeback and forth between the first and second positions, i.e. about the rotation axis B. The actuatorcan be a two way rotary solenoid or stepper motor, or the like, and/or can include a return bias member such as a spring so the actuator is biased toward one extreme position when not energized. Reference is made to to U.S. Pat. No. 9,617,919 (which is incorporated by reference herein in its entirety) for possible examples of low energy multi-position solenoids. Note that the position of the jet tubecan cover not only full-on/off operation but can be positioned proportionally anywhere between the positions offor example, and the rotary actuator can cover operation all the way from either a fixed positionto position, but also varying the position between two positions gradually. Stepper motors can be used which could have very fine increments (e.g. 5° control) which would give good proportionality.

The directional jet systemincludes a housingwith a main inletin fluid communication with an interiorof the housing. The jet tubeincludes at least one inletinside the housingin fluid communication to receive flow from the interiorof the housinginto the jet tube. The rotational actuatoris inside the housing, and is operatively connected to rotate the jet tubebetween the first and second positions around a rotation axis B that is parallel to the axis A defined by the drain outlet, and the main inletextends parallel with or along the axis B, and parallel with the axis A. The main spin surface is planar, however it is also contemplated that the main spin surfacecan be conical, as shown in, converging towards the drain outlet, e.g. to reduce flow angle into the drain outletand reduce pressure loss.

With continued reference to, the rotation actuatorcan be outside of the housingwith a shaftextending into housingoperatively connected to rotate jet tubeinside housing. As shown in, the main inletcan extend lateral to the axis A and to the axis B, wherein the rotational actuatoris operatively connected to rotate the jet tubebetween the first and second positions around a rotation axis B that is oblique to the axis A. In, the main inletextends along or parallel to the axis A defined by the drain outlet, although the rotational actuatoris operatively connected to rotate the jet tubebetween the first and second positions around a rotation axis B that is oblique to the axis A. Seals such as o-ringscan be used to prevent leaking round the porting for the jet tube.

With reference to, a feed armcan be connected in fluid communication with the drain outlet. A spray nozzlecan be connected in fluid communication with the feed armdownstream of the drain outletfor issuing a spray, such as for fuel injection in a gas turbine engine or the like. The feed armand spray nozzleare shown for the configuration of the valve systemas shown in, however those skilled in the art will readily appreciate that the feed armand spay nozzlecan be included in any of the configurations disclosed herein.

With reference now to, the directional jet systemcan include a sealoperatively connected to the spin chamberto seal the jet orificein a third position of the directional jet systemto stop flow into the spin chamberfrom the directional jet system, as shown in, whereshow the first and second positions described above, with corresponding tangential and radial flow arrows, respectively. In addition to or in lieu of a seal, the itemcan be a check valve operatively connected to the spin chamberto check the jet orificein the third position of the directional jet systemto stop flow into the spin chamberfrom the directional jet systembelow a predetermined inlet pressure. The check valve configuration may not require elastomeric seal. Incorporating a completely closed check valve when jet is rotated past spin chamber wall allows valve to open as a port window until the jet is fully exposed, then with continued rotation toward the radial direction, the system can behave like a swirl valve. It is also contemplated that the sealcan be omitted and the jet orificecan simply seal against the wall of the spin chamberin the third position shown in.

With referenced now to, the drain outletcan feed into a hydromechanical piston valve assemblythat includes a pistonwith portsand a biasing memberconfigured to bias the member against pressure flowing through the assembly. When pressure on flow through the assemblyacts on the piston, the pistoncan slide linearly along its axis against the bias of the biasing member. In, the drain outletfeeds into the hydromechanical piston valve assemblyin series with a main flow passagethrough the hydromechanical piston valve assembly, e.g. upstream of the piston. In, the drain outletfeeds into the hydromechanical piston valve assemblyin a side stream that is parallel with a main flow passagethrough the hydromechanical piston valve assembly. In this case, the actuatorrotates the piston, which doubles as the jet tube. The rotational direction of the outlet orificecontrols how much flow can pass through the side stream that includes the drain outlet. The pistonis keyed to the shaftof the actuatorfor rotation by the actuator, but the pistonis free to slide along its axis relative to the shaftof the actuator.

With reference now to, the jet orificecan be fixed relative to the spin chamber. The jet member includes a diverterdownstream from the jet orifice. The diverteris configured to move to divert flow from the jet orificebetween the first position shown infor tangential flow, e.g. where the downstream end of the diverterpoints tangentially around the drain outlet, and the second position shown infor radial flow, e.g. where the downstream end of the diverterpoints to more directly to the drain outlet.

Systems and methods as disclosed herein provide potential benefits including the following. They do not require match grinding to match a piston and a sleeve. They do not need highly calibrated valve porting (the flow profile can be set electronically). They can be used to trim high power or low power. They do not require large forces to hold position—there is no pressure balance except a relatively small thrust from a jet and force to overcome a spring return if included. They can be designed to fail in place, or closed, or open, depending on spring return chosen. They can adjust 30% or more of flow through adjusting the amount of swirl in the swirl chamber. The amount of adjustable flow depends on the size of the jet and amount of offset of the spin chamber e.g. as shown in. They can be turned completely closed (e.g. with or without a check valve) and can have window opening. They can be integrated with existing hydromechanical valves to incorporate full scheduling.

The methods and systems of the present disclosure, as described above and shown in the drawings, provide for controlling flow through a valve system using a directional jet and spin chamber, wherein changing direction of the jet relative to the spin chamber allows for increasing or decreasing flow through the valve system. While the apparatus and methods of the subject disclosure have been shown and described with reference to preferred embodiments, those skilled in the art will readily appreciate that changes and/or modifications may be made thereto without departing from the scope of the subject disclosure.